One conventional exhaust gas recirculation (EGR) system for compression ignition internal combustion engines uses two actuators. The first actuator creates a pressure differential in the intake conduit that draws exhaust gas from the exhaust conduit into the intake conduit where it mixes with the intake charge. The second actuator regulates the flow rate of exhaust gas in the exhaust conduit that is drawn into the intake conduit by the first actuator.
Another conventional EGR system employs a single actuator to regulate the flow rate of exhaust gas drawn into the intake conduit from the exhaust conduit. A stationary throttling device is located in the exhaust conduit to promote the flow of exhaust gas into the intake conduit. The negative pressure pre-existing in the intake conduit created during the intake stroke of the engine provides the pressure differential needed to draw the exhaust gas into the intake conduit.